This invention relates to a horizontal type continuous pug mill for high viscous material and particularly to an improvement of the construction of a continuous polymerizing apparatus for making polycondensation reaction of a synthetic resin, such as polyester. The following description will be given by reference to a continuous polymerizing apparatus.
A conventional horizontal continuous polymerizing apparatus of multi-disk type is arranged such that a monomer material to be polymerized and which has a viscosity of several poises is supplied from an inlet nozzle at one end of the apparatus into a body thereof to polymerize it by pugging and then is discharged from an outlet nozzle at the other end of the apparatus. The pugging of the monomer is effected by rotation of agitating blades within the body under the condition of a vacuum of several Torr (1 Torr being 1 mmHg) and at a temperature of about 280.degree. C. What is raised as a problem in such a case is that when the polymerization of the monomer to be treated progresses to rise its viscosity up to several hundreds poises, the material once stuck to an agitating blade or blades is rotated together therewith thereby causing a stagnation area or areas of the material on a surface or surfaces of the blade or blades. When the material to be treated is stuck on the surface of the blade, the surface refreshing effect of the material is lowered to increase its film thickness and obstract diffusion of the volatile substance, and therefore there are disadvantages that the reaction is required for a relatively long time and that the residence time of the material in the body becomes uneven to degrade the products.